DP-PROJECTIVE MODULES AND DIMENSIONS

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Öz

In this paper, we introduce the notion of DP-projective modules.
It is shown that a left R-module M over a ring R is DP-projective if and only if
it is a cokernel of a Ding projective preenvelope f : A → B with B projective.
It is also shown that a ring R is semisimple if and only if every module is
DP-projective. Moreover, we investigate (global) DP-projective dimensions of
modules and rings. It is shown that l.DP-dim(R) = l.DP-ID(R). In addition,
other applications of those dimensions defined in this way are presented.